Suicide assisted by right-to-die associations: a population based cohort study.

BACKGROUND In Switzerland, assisted suicide is legal but there is concern that vulnerable or disadvantaged groups are more likely to die in this way than other people. We examined socio-economic factors associated with assisted suicide. METHODS We linked the suicides assisted by right-to-die associations during 2003-08 to a census-based longitudinal study of the Swiss population. We used Cox and logistic regression models to examine associations with gender, age, marital status, education, religion, type of household, urbanization, neighbourhood socio-economic position and other variables. Separate analyses were done for younger (25 to 64 years) and older (65 to 94 years) people. RESULTS Analyses were based on 5 004 403 Swiss residents and 1301 assisted suicides (439 in the younger and 862 in the older group). In 1093 (84.0%) assisted suicides, an underlying cause was recorded; cancer was the most common cause (508, 46.5%). In both age groups, assisted suicide was more likely in women than in men, those living alone compared with those living with others and in those with no religious affiliation compared with Protestants or Catholics. The rate was also higher in more educated people, in urban compared with rural areas and in neighbourhoods of higher socio-economic position. In older people, assisted suicide was more likely in the divorced compared with the married; in younger people, having children was associated with a lower rate. CONCLUSIONS Assisted suicide in Switzerland was associated with female gender and situations that may indicate greater vulnerability such as living alone or being divorced, but also with higher education and higher socio-economic position.